His partner is reported to have discovered his remains in the hallway of her home in Los Angeles on Wednesday night.

In a statement to Independent.ie, O'Neill's manager Greg Meyer said: "He was a great guy who was very funny and engaging as well as a very talented actor. He was also an expert equestrian horse trainer."

An autopsy is due to be carried out but his death is not being treated as suspicious, according to TMZ.

Alan O'Neill (left) pictured with Keith Duffy

O'Neill became a household name here with his role as Keith McGrath in RTÉ's Fair City, which he starred in between 2006 and 2012.

He then moved to Hollywood and won a legion of fans when he played Hugh in the cult TV show Sons of Anarchy.

As reports of his death emerged, shocked friends and fans took to social media to share fond memories of Alan.

Irish actress Jenny Dixon said in a touching twitter post that it was a "privilege" to have known O'Neill.

She wrote: "One of the first films I did & a privilege to act across from @AlanONeill19.

"A great friend who taught me so much. Thank you for your kindness. So very sorry to hear of your passing. A great man, sadly missed.

"My thoughts & prayers to you & to your family."

One of the first films I did & a privilege to act across from @AlanONeill19 .A great friend who taught me so much. Thank you for your kindness. So very sorry to hear of your passing. A great man, sadly missed. My thoughts & prayers to you & to your family pic.twitter.com/Kygj7pybWo

RTE's Fair City issued the following statement: “All of us are so deeply saddened to hear this terribly sad news. Alan was a breath of fresh air on set, always full of energy and passion. He was an absolute joy to work with.

"During his time on Fair City his contribution to both his character and the production was always peppered with an enthusiasm that became infectious, he will be missed greatly by all in Carrigstown.

"His family and friends are in our thoughts and this very difficult time."

Jane Gogan, Head of RTÉ Drama added, “Alan was a kind, funny and gentle person who showed great courage in his career as a actor. My deepest sympathies to his family and friends”.